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Elephant endotheliotropic herpesviruses (EEHVs) have co-existed with elephants for millions of years, yet may cause fatal haemorrhagic disease (EEHV-HD), typically in elephants between 1 and 10 years of age. EEHV is omnipresent in (sub)adult elephants, and young elephants with low EEHV-specific antibody levels are at risk for EEHV-HD, suggesting that fatal disease may occur due to an insufficiently controlled primary infection. To further address this hypothesis, sera of three large elephant cohorts were subjected to a multiple EEHV species ELISA: (I) 96 Asian elephants between 0 and 57 years, including 13 EEHV-HD fatalities, from European zoo herds typically sized five to six elephants, (II) a herd of 64 orphaned elephants aged 0-15 years at the Elephant Transit Home in Sri Lanka and (III) 31 elephants aged 8-63 years, part of a large herd of 93 elephants at Pinnawala Elephant Orphanage, Sri Lanka. All Sri Lankan elephants showed high EEHV-specific antibody levels regardless of their age. While antibody levels of most European zoo elephants were comparable to those of Sri Lankan elephants, the average antibody level of the European juveniles (1-5 years of age) was significantly lower than those of age-matched Sri Lankan individuals. Moreover, the European juveniles showed a gradual decrease between 1 and 4 years of age, to be attributed to waning maternal antibodies. Maintenance of high levels of antibodies in spite of waning maternal antibodies in young Sri Lankan elephants is likely due to the larger herd size that increases the likelihood of contact with EEHV-shedding elephants. Together with the observation that low levels of EEHV-specific antibodies correlate with increased numbers of EEHV-HD fatalities, these results suggest that infection in presence of high maternal antibody levels may protect calves from developing EEHV-HD, while at the same time activating an immune response protective in future encounters with this virus., (© 2022 The Authors. Transboundary and Emerging Diseases published by Wiley-VCH GmbH.)

Calodium hepaticum infection is rarely reported in carnivores. We describe two cases of C. hepaticum infection, causing liver lesions, in wild jungle cats ( Felis chaus ) in Sri Lanka.

In this paper, the performance of nano-porous electrodes made of a composite material of SrTiO3 and SnO2 are compared with those made of bare SnO2. When these particular devices are analyzed in a comparative mode the results confirmed the enhancement of photovoltaic parameters in the former device. The performance of respective cells were examined by several methods including I-V characteristic measurements, photocurrent action spectra, dark I-V measurements, Mott-Schottky measurements and X-ray diffraction measurements. Even though such improvements in this particular cell could be explicated by the formation of a potential energy barrier of SrTiO3 particles of comparably large width at the SrTiO3/SnO2 interface, the passivation of voids in the SnO2 film by SrTiO3 particles to a certain extent could not be totally ruled out. Besides, high energetic electrons injected by dye molecules move more credibly through mini-bands formed in the chain of nano-crystalline SnO2 particles to the back contact. The blocking of the recombination path and the shifting up of the uppermost electron occupied level of SnO2 accompanying the conduction band edge in the SrTiO3/SnO2 composite film, may have lead to the observed enhancement of the fill factor and photovoltage, respectively., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A dye-sensitized heterojunction of configuration n-TiO2/PD-CuPC-MV/p-CuSCN (where PD = 3,4-pyridinedicarboxylic acid anchored to TiO2, CuPC = copper(II) phthallocyanine tetrasulfonic acid ionically linked to PD, and MV = Methyl Violet complexed to CuPC) is developed to demonstrate the applicability of molecular rectification to dye-sensitized solar cells as a strategy of suppressing recombination. Short-circuit photocurrent, open-circuit voltage, energy conversion efficiency, and incident photon to photocurrent conversion of this system are higher than that of the heterojunctions of configurations n-TiO2/PD-MV/p-CuSCN, n-TiO/CuPC-MV/p-CuSCN, and n-TiO2/MV/p-CuSCN. The impressively high rectification ratio and the mode of anchorage of CuPC toTiO2 are suggested as the cause of superior photovoltaic action of the cell TiO2/PD-CuPC-MV/p-CuSCN.

It is shown that an ionic dye Y can be electrostatically bonded to an ionic molecule X of opposite charge anchored to a TiO2 surface via suitable ligands. Dye-sensitized solid-state photovoltaic cells of the configuration n-TiO2/X-Y/p-CuSCN were constructed with X = trihydroxybenzoic acid or mercurochrome and Y = methyl violet. Cells of this configuration were found to be more efficient and delivered higher short-circuit photocurrents and open-circuit photovoltages compared to the cells based only on methyl violet or mercurochrome. It is suggested that this technique would be a means of extending the spectral response of dye-sensitized photovoltaic devices. The formation of a wider barrier by coupling of anionic and cationic species also improves the cell performance by suppression of recombination.

The anionic dye Rose Bengal was found to surface chelate more strongly to SnO2 nanocrystalline films previously kept immersed in a solution of washed and dried AlCl3. Dye-sensitized photoelectrochemical cells made from such films exhibit enhanced quantum and energy conversion efficiencies. The result is explained as caused by binding of AlCl3 to SnO2 surface by elimination of Cl atoms and stronger bonding of Rose Bengal to Al, enhancing dye adsorption and suppression of back electron transfer by bridging of an Al atom between Sn and the dye molecule.